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An immunocompetent child in Canada received a diagnosis of disseminated alveolar Echinococcus multilocularis infection. The case lacked typical features of liver involvement and was possibly related to a rare congenital portosystemic shunt. We summarize the rapidly evolving epidemiology of E. multilocularis parasites in Canada.

This report is part of the Echinococcus multilocularis surveillance scientific reports which are presented annually by EFSA to the European Commission and are intended to assess the sampling strategy, data collection and detection methods used by Finland, Ireland, United Kingdom (Northern Ireland) and Norway in their respective surveillance programmes. The surveillance programmes of these four countries were evaluated by checking the information submitted by each of them and verifying that the technical requirements were fulfilled as laid down in Commission Delegated Regulation (EU) 2018/772 of 21 November 2017 supplementing Regulation (EU) No 576/2013 of the European Parliament and of the Council with regard to preventive health measures for the control of Echinococcus multilocularis infection in dogs, and repealing Delegated Regulation (EU) No 1152/2011. The information was divided in four different categories for assessment: the type and sensitivity of the detection method, the selection of the target population, the sampling strategy and the methodology. For each category, the main aspects that need to be considered in order to accomplish the technical requirements of the legislation were checked against compliance of several criteria. Three of the countries participating in this surveillance (Finland, Ireland and Norway (mainland)) succeeded in the fulfilment of the technical legal requirements foreseen in Commission Delegated Regulation (EU) 2018/772 concerning these four different categories. Northern Ireland did not fulfil those requirements, not even assuming a diagnostic test sensitivity value of 0.99 (value provided by the national reference laboratory, higher than the conservative sensitivity value suggested by EFSA, i.e. 0.78). None of the four countries recorded positive samples in the 12‐month reporting period.

Cases of alveolar echinococcosis (liver cyst) caused by Echinococcus multilocularis are rare in the UK, but are increasing secondary to migration and travel. We report a case of alveolar echinococcosis that presented clinically as a cholangiocarcinoma. At histology, vesicles unusually contained protoscoleces, a feature more commonly seen in cases of Echinococcus granulosus. PCR confirmed the organism as E. multilocularis, avoiding misdiagnosis and subsequent mismanagement.

Een twee jaar oude labrador retriever uit de Franse Alpen werd aangeboden omwille van een opgezet abdomen, lethargie en gewichtsverlies. Op computertomografisch onderzoek werd een grote, cavitaire levermassa vastgesteld die de vena cava caudalis in groeide en die geassocieerd was met multipele gelijkaardige laesies ter hoogte van de lever, alsook met longnodulen en lymfadenopathie. Initieel werd deze aandoening verkeerdelijk aanzien als een maligne neoplasie, maar cytologisch en histologisch onderzoek van de grootste levermassa was compatibel met een cestodeninfectie. Een PCR-test bevestigde een infestatie met Echinococcus multilocularis. Medicamenteuze therapie met albendazole werd opgestart. De hond bleef klinisch goed gedurende tien maanden na de diagnose, maar moest worden geeuthanaseerd omdat de eigenaars terug moesten keren naar Groot-Brittannie en ze niet legaal kon geimporteerd worden. Volgens de auteurs is dit de eerste casereport waarin een langetermijnopvolging wordt beschreven van een Echinococcus sp.-infectie bij een hond, die medicamenteus behandeld werd. Dit geval toont ook aan dat medicamenteuze therapie een bruikbare optie is als chirurgie niet haalbaar is.

The resistance/susceptibility to Echinococcus multilocularis infection in mice is genetically controlled. However, genetic factors responsible for these differences remain unknown. Our previous study in genetic linkage analysis has revealed that there is a significant quantitative trait locus (QTL) for the establishment of cyst (Emcys1), and a highly significant QTL for the development of protoscolex of E. multilocularis larvae (Empsc1), on mouse chromosomes 6 and 1, respectively. The current study aimed to confirm these QTLs and narrow down the critical genetic region that controls resistance/susceptibility to E. multilocularis infection by establishing congenic and subcongenic lines from C57BL/6 (B6) and DBA/2 (D2) mice. For protoscolex development phenotype, two congenic lines, B6.D2-Empsc1 and D2.B6-Empsc1 were developed, where responsible QTL, Empsc1 was introgressed from D2 into B6 background and vice versa. For cyst establishment phenotype, two congenic lines, B6.D2-Emcys1 and D2.B6-Emcys1 were developed, where responsible QTL, Emcys1 was introgressed from D2 into B6 background and vice versa. Because there was no significant difference in cyst establishment between B6.D2-Emcys1 and D2.B6-Emcys1 mice after challenge with E. multilocularis, it is suggested that the Emcys1 does not solely control the cyst establishment in mouse liver. However, infection experiments with B6.D2-Empsc1 and D2.B6-Empsc1 mice showed a significant difference in protoscolex development in the cyst. It confirms that the Empsc1 controls phenotype of the protoscolex development in the cyst. Subsequently, two subcongenic lines, B6.D2-Empsc1.1 and B6.D2-Empsc1.2 from B6.D2-Emcys1 and one subcongenic line, D2.B6-Empsc1.1 from D2.B6-Empsc1 were developed to narrow down the critical region responsible for protoscolex development. From the results of infection experiments with E. multilocularis in these subcongenic mice, it is concluded that a gene responsible for protoscolex development is located between D1Mit290 (68.1 cM) and D1Mit511 (97.3 cM).

This report is part of the ‘Echinococcus multilocularis surveillance’ scientific reports which are presented annually by EFSA to the European Commission and are intended to assess the sampling strategy, data collection and detection methods used by Finland, Ireland, the United Kingdom (UK) and Norway in their respective surveillance programmes. The surveillance programmes of these four countries were evaluated by checking the information submitted by each of them and verifying that the technical requirements were fulfilled as laid down in Commission Delegated Regulation (EU) 2018/772 of 21 November 2017 supplementing Regulation (EU) No 576/2013 of the European Parliament and of the Council with regard to preventive health measures for the control of Echinococcus multilocularis infection in dogs, and repealing Delegated Regulation (EU) No 1152/2011. The information was divided into four different categories for assessment: the type and sensitivity of the detection method, the selection of the target population, the sampling strategy and the methodology. For each category, the main aspects that need to be considered in order to accomplish the technical requirements of the legislation were checked against compliance of several criteria. All the countries participating in this surveillance (Finland, the UK, Ireland and Norway) succeeded in the fulfilment of the technical legal requirements foreseen in Commission Delegated Regulation (EU) 2018/772 concerning these four different categories. Within the UK, Northern Ireland fulfils those requirements only when assuming a diagnostic test sensitivity value of 0.99, provided by the national reference laboratory, which is higher than the sensitivity value suggested by EFSA (conservative value of 0.78). None of the four countries recorded positive samples in the 12‐month reporting period. It should be noted that Malta did not have to report surveillance data in order to maintain its eligibility to continue applying preventive health measures for the control of E. multilocularis infection in dogs entering its territory, but to meet the conditions laid down in Article 4(1) of Commission Delegated Regulation (EU) 2018/772 including the submission of evidence to the European Commission of the absence of the red fox from the territory.

Echinococcus multilocularis metacestodes mainly reside in liver in humans and animals, and cause serious damages. UBE2N was herein shown to be downregulated in response to the infection. UBE2N was further shown to be predominantly expressed in the hepatocytes, which was also significantly downregulated during the infection. UBE2N was a target of emu-miR-4989, which was loaded into the exosomes secreted by parasites. These emu-miR-4989-encapsulating exosomes were internalized by hepatocytes, and induced a significant decrease of relative luciferase activity in the cells transfected with the construct containing a wild type of UBE2N 3'-UTR compared to the control (p0.05). These results demonstrate that emu-miR-4989 is involved in the UBE2N inhibition in the hepatocytes during E. multilocularis through exosomes.

Natural infection with larval Echinococcus multilocularis was recognized in one of eight Norway rats, Rattus norvegicus, caught indoors in 2009 in Ebetsu, Hokkaido, northern Japan. Cystic lesions were found in the right median and lateral lobes of the liver, with numerous alveolar cysts in the periphery of the lesions. Protoscolices were formed within large cysts. The laminated layers of the cysts were positive for PAS staining. Nested PCR using the primers specific for Taenia mitochondrial 12S rDNA yielded a 250-bp product, and the sequence of the PCR product matched that of E. multilocularis isolates from Hokkaido and Germany. This is the third natural alveolar hydatidosis in R. norvegicus in Japan.

A cross-sectional survey was performed to obtain first information on the prevalence of Echinococcus multilocularis infection in slaughter horses from central, eastern and southern Poland, a country with a highly endemic occurrence of this tapeworm in red foxes. White tough nodular lesions being 3–10 mm in size, sharply demarcated and spherically or irregularly shaped were found in 54 of 365 livers examined. Histologically, focal granulomatous necrotizing inflammations and sometimes PAS-positive acellular lamellar structures being characteristic of the E. multilocularis metacestode stage were visible; protoscoleces were not found. E. multilocularis DNA was detected in six of 19 hepatic lesions examined by nested PCR. Our results from molecular and morphological diagnostics suggest an overall prevalence of alveolar echinococcosis between 4.7% and 14.8% in the horse population studied. Horses as dead-end hosts do not play any role in the life cycle of E. multilocularis but may serve as additional sentinel animals in monitoring the environmental contamination with tapeworm eggs.

Alveolar echinococcosis is a parasitic disease limited to the northern hemisphere. The disease occurs primarily in the liver and shows a profile mimicking slow-growing malignant tumors. Echinococcus multilocularis infection is fatal if left untreated. It can cause several complications by infiltrating the vascular structures, biliary tracts, and the hilum of the liver. As it can invade the adjacent organs or can spread to distant organs, alveolar echinococcosis can easily be confused with malignancies. We provide a brief review of epidemiologic and pathophysiologic profile of alveolar echinococcosis and clinical features of the disease. This article focuses primarily on the imaging features of alveolar echinococcosis on ultrasonogra-phy, computed tomography, magnetic resonance imaging, diffusion-weighted imaging and positron emission tomography-computed tomography. We also reviewed the role of radiology in diagnosis, management, and follow-up of the disease.

The aim of the study was to estimate the current prevalence of E. multilocularis in selected populations of red foxes in Poland and to evaluate the changes in prevalence of this parasite by comparison with the results obtained in the same area during earlier surveillance. The investigations were performed in the area of four Polish provinces: 2 eastern/south-eastern (Lubelskie and Podkarpackie) and 2 south-western (Śląskie and Opolskie). Five hundred red foxes coming from the investigated areas were examined between 2013 and 2014 to estimate the current situation in selected provinces. Moreover, 550 red foxes from the same areas examined between 2007 and 2013 were used for comparison of differences in E. multilocularis prevalences in time. Intestines were examined with the use of the sedimentation and counting technique. Among 500 foxes examined in the current study, 118 were positive for E. multilocularis. There were differences in prevalence between individual provinces: Podkarpackie Province - 54.6%, Lubelskie Province - 18.9%, Śląskie Province - 11.7%, and Opolskie Province - 3.9%. Statistical analysis demonstrated that in most cases there were no differences in prevalence between the current results and the results from previous studies. Only in Opolskie Province was a statistically significant increase observed between 2010 and 2014. A stable degree of infection in the region with high prevalence of this parasite was demonstrated. However, a significant increase in the region with very low prevalence of E. multilocularis points out the necessity to monitor this infection during the coming years to control the progress of the disease

Heavy metal (Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) levels in red fox small intestine samples with or without Echinococcus multilocularis infection were studied. The red foxes were taken from the open countryside of northwest Bohemia (CR). Red foxes with E. multilocularis infection had lower levels of toxic metals (Cd, Pb); cadmium levels in infected foxes (0.0052 mg/kg) were twice as low as in uninfected foxes (0.0106 mg/kg). This was the same case for lead: 0.0288 mg/kg infected red foxes (inf.) and 0.0413 mg/kg uninfected (uninf.). Conversely, red foxes with E. multilocularis infection yielded higher concentrations in comparison to their uninfected counterparts: Cr (0.0087 mg/kg uninf. and 0.0116 mg/kg inf.), Cu (0.2677 mg/kg uninf. and 0.3205 mg/kg inf.), Fe (6.46 mg/kg uninf. and 10.89 mg/kg inf.), Mn (0.1966 mg/kg uninf. and 0.2029 mg/kg inf.), Ni (0.0415 mg/kg uninf. and 0.064 mg/kg inf.) and Zn (16.71 mg/kg uninf. and 20.25 mg/kg inf). This could support the hypothesis that tapeworms are able to absorb toxic heavy metals from the host body into their tissues, as well as to modify other element concentrations in the host body.

The aim of this study was to demonstrate characteristic imaging and accurate evaluation of blood perfusion in early stage of hepatic alveolar echinococcosis (HAE) by contrast-enhanced ultrasonography (CEUS). The early stage of experimentally induced secondary HAE in 45 rats was studied. Thirty-six HAE lesions in 33 rats, confirmed by pathologic examination, were examined by ultrasound (US), color Doppler flow imaging (CDFI) and then CEUS. Thirty-three lesions were found in 30 rats by US, and 30 lesions were detected in 27 rats by CEUS. The sensitivity of US and CEUS was 92% (95% CI 76%–98%) and 82% (95% CI 65%–93%), respectively. US imaging characteristics were categorized into four types: hyperechoic spot (type 1, 45.5%, 15/33), granular hyperechoic spots (type 2, 12.1%, 4/33), hyperechoic lesion (type 3, 30.3%, 10/33) and mixed pattern (type 4, 12.1%, 4/33). CDFI failed to detect blood flow signals in any lesions. CEUS results for 30 lesions showed ring enhancement in the peripheral area during the arterial phase and no filling effect in either the portal or the delayed phase (46.7%, 14/30); ring enhancement combined with central septa enhancement during the arterial phase and portal venous phase (46.7, 14/30), and no enhancement (6.6%, 2/30). The enhanced area, confirmed by pathologic examination, was an inflammatory reaction belt surrounding the lesion. The results of this study suggest that US, with high sensitivity, can be used as a screening method for early HAE lesions in the animal model, while CEUS can be used for displaying the peripheral blood perfusion and vesicle structure.

The European Food Safety Authority (EFSA) was required to support the European Commission in preparing the review of Regulation (EU) No 1152/2011. In Europe, red fox (Vulpes vulpes) is the main definitive host of the Echinococcus multilocularis (EM) lifecycle. There is no evidence that any other carnivore species can maintain the lifecycle in the absence of red fox, and this makes it to most relevant target species for surveillance. Movement of infected definitive hosts is an important introduction pathway. The knowledge on the geographical distribution of the environmental factors for the persistence of the lifecycle is scarce. In areas where no suitable autochthonous wild canid hosts and no highly suitable intermediate hosts are present, e.g. Malta, establishment of the EM cycle is considered close to impossible. Such countries do not need to carry out surveillance on domestic dogs to substantiate absence of EM in the relevant animal population. Reconsideration of some aspects of the current legislation regarding surveillance activities might be relevant; for example the identification of epidemiologically relevant units should be independent from political borders. Studies to improve the knowledge on epidemiological risk factors should be encouraged to enable risk-based sampling. Echinococcus notification should always be done at species level in order to discriminate between the more severe alveolar echinococcosis and the cystic echinococcosis. Praziquantel is the substance of choice for the treatment of dogs. However, the treatment window should be reconsidered to reduce the risk of re-infection: a general rule is to treat as close as possible to entry into a non-infected country. There is a lack of standardization of the diagnostic methods between laboratories. The diagnostic sensitivity of the tests should be established in accordance to the World Organisation for Animal Health (OIE) standards for validation. For the time being, the diagnostic sensitivity can be set conservatively to 78%.

Echinococcus multilocularis is a tapeworm responsible in its larval stage for alveolar echinococcosis, a disease which is lethal when left untreated. Multivesiculated parasitic lesions in the liver were diagnosed at necropsy in a captive-born nutria (Myocastor coypus) and in a ring-tailed lemur (Lemur catta) which had been in a French zoo for 16months. Molecular analyses confirmed the diagnosis of E. multilocularis obtained by histological analyses. These were the first cases of infection by E. multilocularis reported in lemurs in Europe, and the first case in nutria in European enclosures. Lemurs are confirmed to be particularly sensitive to E. multilocularis with a massive infection. In both cases, the infection appears to have been contracted in the zoo indirectly via environmental contamination by feces from roaming foxes. Due to the large endemic area for E. multilocularis, the increasing prevalence in foxes in France, and an increase in awareness of the disease, other cases of infection in captive animals will probably be recorded in France in the coming years.

A 33 month-old male flying squirrel kept in a zoo developed progressive dyspnea and died. Macroscopically, the liver and lung were enlarged with numerous nodular vesicles. Histologically, these organs were replaced by numerous collapsed vesicles demarcated by fibrous tissues. The cysts lined by a cellular, germinal layer contained numerous brood capsules with abundant production of well-developed protoscolices. Protoscolices were about 80-100 μm in diameter, and had hooks being visible as refractive structures. This zoo locates in the east of Hokkaido where is an endemic area of Echinococcus multilocularis infection. From epidemiology and pathological findings, this animal was diagnosed as E.multilocularis infection. This report describes the pathology of the first case of E. multilocularis infection in a flying squirrel.

Infections of humans with Echinococcus multilocularis, the causative agent of alveolar echinococcosis (AE), a zoonosis, have been described with increasing frequency in Poland since 1994. In the attempt to verify these reports, we analyzed specimens obtained from a representative group of Polish patients. Liver lesions in patients with AE that was diagnosed on the basis of results of histological and serological tests contained E. multilocularis DNA, as shown by the presence of specific microsatellite sequences and mitochondrial 12S rDNA. The same tests clearly distinguished between AE and cystic echinococcosis, which is caused by Echinococcus granulosus. These data are unequivocal proof that human infections with E. multilocularis occur in Poland.

By the end of the 1980s the only reliable technique for diagnosing the intestinal Echinococcus multilocularis infection of definitive hosts was parasite detection at necropsy. Currently, several techniques for the post mortem and in vivo diagnosis are available, including classical and modern methods. The sedimentation and counting technique (SCT) is used for the exact determination of the worm burden in the intestine after necropsy. The SCT has high sensitivity and specificity values (both close to 100%) and can be regarded as ‘gold standard’. The principle of the intestinal scraping technique (IST) is the stereomicroscopic examination of at least 15 intestinal thick smears. This technique has a sensitivity of 78% and a specificity approximating 100%. In recent years, the IST has been successfully used in large post mortem surveys of foxes for E . multilocularis . The newer techniques for detecting coproantigens by ELISA (CA-ELISA) exhibit rather high sensitivities between 84 and 95%, combined with very high specificities of >96%, the latter regarding non- Echinococcus cestodes and other parasites. However, cross-reactivity may occur with E. granulosus . Copro-DNA detection by PCR is also highly sensitive (89–94%) and specific (100%). With the SCT, IST and Copro-PCR one person can only examine about 10–20 animals per day, whereas the CA-ELISA allows the examination of 200 samples. Therefore, the latter test is suited for mass-screening of definitive host populations. Both the CA-ELISA and the Copro-PCR allow the examination of materials from dead and living animals, including faecal samples collected in the field. Quite often diagnostic techniques have been used without adequate quality control and proper definition of their performance characteristics, including diagnostic sensitivity, specificity, predictive values and some other parameters. Examples are presented with the aim to demonstrate the need and the value of calculating the predictive values for assays used to diagnose the E. multilocularis infection in individual animals and in definitive host populations.

Characterizing the force of infection (FOI) is an essential part of planning cost effective control strategies for zoonotic diseases. Echinococcus multilocularis is the causative agent of alveolar echinococcosis in humans, a serious disease with a high fatality rate and an increasing global spread. Red foxes are high prevalence hosts of E. multilocularis. Through a mathematical modelling approach, using field data collected from in and around the city of Zurich, Switzerland, we find compelling evidence that the FOI is periodic with highly variable amplitude, and, while this amplitude is similar across habitat types, the mean FOI differs markedly between urban and periurban habitats suggesting a considerable risk differential. The FOI, during an annual cycle, ranges from (0.1,0.8) insults (95% CI) in urban habitat in the summer to (9.4, 9.7) (95% CI) in periurban (rural) habitat in winter. Such large temporal and spatial variations in FOI suggest that control strategies are optimal when tailored to local FOI dynamics., Author Summary Human alveolar echinococcosis (AE) is caused by the fox tapeworm E. multilocularis and has a high fatality rate if untreated. The frequency of the tapeworm in foxes can be reduced through the regular distribution of anthelmintic baits and thus decrease the risk of zoonotic transmission. Here, we estimate the force of infection to foxes using a mathematical model and data from necropsied foxes. The results suggest that the frequency of anthelmintic baiting of foxes can be optimised to local variations in transmission that depend upon season and type of fox habitat.

Echinococcus multilocularis, the causative agent of alveolar echinococcosis, is spreading geographically in Europe, and prevalence rates in foxes, the final host, are increasing. Concomitantly, the rate of newly diagnosed human infections has already doubled in Germany. We report a cluster of alveolar echinococcosis in 24 animals of different Old World monkey species (15 cynomolgus monkeys, 5 rhesus monkeys, and 4 lion-tailed macaques) in northern Germany. The cluster described is the largest ever recorded in a single center. Cynomolgus monkeys were very susceptible and constituted the monkey species at highest risk, indicating that this species could act as a sentinel animal for the transmission of alveolar echinococcosis in zoological gardens or similar institutions.

Detection of Echinococcus multilocularis coproantigen using sandwich enzyme-linked immunosorbent assay (sELISA) was performed on fecal samples of red foxes. Fecal samples were obtained from the rectum of shot foxes. The antibodies used for sELISA recognize heat-resistant antigens, thus all fecal samples were heated to render it safe for handling before examination. E. multilocularis infection in shot foxes were evaluated by the detection of adult worms in the distal one-sixth portion of the small intestine. Among 103 positive cases out of 430 foxes in a necropsy in 1993, 90 samples were also coproantigen positive (the sensitivity is 87.4%). In 11 out of 13 coproantigen negative cases, less than 10 worms were detected at necropsy. These results suggest that detection of coproantigen is useful for field surveys of foxes naturally infected with E. multilocularis.

Background Alveolar echinococcosis is a zoonotic disease caused by the metacestode of Echinococcus multilocularis. Many species of small mammals, including arvicolid rodents or Ochotona spp., are natural intermediate hosts of the cestode. The main aim of this study was to identify natural intermediate hosts of E. multilocularis in Chenaran County, Razavi Khorasan Province, northeastern Iran, where the prevalence of infected wild and domestic carnivores is high. Methodology/Principal Findings A program of trapping was carried out in five villages in which this cestode was reported in carnivores. The livers of 85 small mammals were investigated for the presence of E. multilocularis infection using multiplex PCR of mitochondrial genes. Infections were identified in 30 specimens: 23 Microtus transcaspicus, three Ochotona rufescens, two Mus musculus, one Crocidura gmelini, and one Apodemus witherbyi. Conclusions/Significance A range of small mammals therefore act as natural intermediate hosts for the transmission of E. multilocularis in Chenaran County, and the prevalence suggested that E. multilocularis infection is endemic in this region. The existence of the life cycle of this potentially lethal cestode in the vicinity of human habitats provides a significant risk of human infection., Author Summary Small mammals, especially rodents, coexist with humans, particularly in rural areas where they become infected with the larval stages of Echinococcus multilocularis via ingestion of eggs in feces from infected carnivores. As prey for carnivores, small mammals have an important role in the life cycle of E. multilocularis, the agent of a serious zoonotic disease, alveolar echinococcosis, infecting people in most northern hemisphere countries. We detected E. multilocularis infection in the liver of small mammals in villages of the Chenaran region of northeastern Iran, where we previously found adult E. multilocularis and/or eggs in all wild, and some domestic, carnivores examined. Several species of small mammals, especially the Transcaspian vole (Microtus transcaspicus), were natural hosts of this cestode. Since infected voles are a good marker of soil contamination with E. multilocularis eggs, they are an indicator of the infection risk for inhabitants. There is a need to educate local populations about risk of infection to avoid transmission of this pathogenic parasite.

International audience; During 2005-2010, we investigated Echinococcus multilocularis within fox populations in a large area in France. The parasite is much more widely distributed than hitherto thought, spreading west, with a much higher prevalence than previously reported. The parasite also is present in the large conurbation of Paris.

In the Jura mountains, Plateau and Alps of western Switzerland important variations in the prevalence of Echinococcus multilocularis infection in red foxes were observed between geographical areas from 1990 to 1995. The Jura mountains and the Plateau had higher mean prevalence levels than the Alps with 30.6, 32.4 and 18.8%, respectively. The highest rate was recorded in the Plateau in the canton of Fribourg with a prevalence of 52.3%. The prevalence of E. multilocularis infection in foxes in the alpine canton of Valais was the lowest (7.1%). Juvenile foxes were found to be more susceptible to E. multilocularis than adults. Adult foxes were less heavily infected in summer and autumn, while the prevalence in juveniles (less than 1 year old) increased between the spring and winter, when they are more than 6 months old. The retrospective data relate to the beginning of the 1990s, since when a drastic prevalence increase of E. multilocularis infection in foxes has occurred in several regions of Europe. Nevertheless, the study is a major contribution to the epidemiological situation of E. multilocularis in central Europe, in that it contains valuable information on spatial distribution and seasonal differences in different age groups of foxes.

Alveolar echinococcosis (AE) is a severe zoonotic disease caused by the metacestode stage of Echinococcus multilocularis. The infection can have fatal consequences in humans if treatment is not provided, so early diagnosis is fundamental for initiating treatment and reducing morbidity and mortality. In addition, detection of the parasite in the definitive host plays a central role in epidemiological studies and surveillance programmes for control of AE. This review presents an overview of the present situation regarding the immunodiagnosis of E. multilocularis infection. Special attention is given to the description of the native, partially purified and recombinant antigens available currently for immunodiagnostic purposes. Recent advances in the primary serodiagnosis and follow-up of AE patients are highlighted, including the detection of specific cytokine profiles. Progress in the immunodiagnosis of intestinal E. multilocularis infection in definitive hosts, particularly the detection of excretory–secretory and integument products of the worm in faeces (copro-antigens) by ELISA, is also discussed.

Anthelmintic (praziquantel) baiting of wild red foxes against Echinococcus multilocularis infection was studied in a highly epizootic suburban area of Otaru, Hokkaido (the northern island of Japan) during the summer and autumn in the years 1999-2004. Acceptance of baits containing the biomarker tetracycline (TC) was evaluated. The prevalence of E. multilocularis infection in foxes before baiting (1999-2000) was 58% (88/153), whereas in the fourth year of bait distribution year (2004), it decreased to 11% (5/45). Analysis of TC marking in the teeth of foxes showed that 39% (77/195) of those captured after baiting were estimated to have consumed baits in the year of capture. Importantly, more juvenile (56%, 49/87) than adult foxes (26%, 28/108) were marked, indicating efficient baiting of juveniles, which tended to have a higher worm burden of E. multilocularis. Of 77 marked foxes, E. multilocularis and Alaria alata (monitored as the second indicator species of deworming) were not detected in 70 (90%) and 76 (99%) foxes, respectively. The results suggest effective deworming by bait consumption. However, it was also demonstrated that 9% of the marked foxes were infected or re-infected after bait consumption, suggesting high infection pressure and the importance of frequent baiting.

Detection of Echinococcus coproantigen using sandwich enzyme-linked immunosorbent assay (sELISA) was performed on fecal samples of red foxes in Hokkaido, Japan. Fecal samples were collected around fox dens in 1990 and 1992. The antibodies used for sELISA recognize heat-resistant antigens, thus all fecal samples were heated to render it safe for handling before examination. Detection of taeniid egg in fox feces collected was considered as an indication of E. multilocularis infection. In fecal samples collected in 1990 and 1992, coproantigen positive results out of taeniid-egg positive cases were 38/40 (95.0%) and 95/97 (97.9%), respectively. In addition, coproantigen was detected regardless of fecal condition when collected from the field, suggesting that the antigens detected by this method are quite stable. These results suggest that detection of coproantigen is useful for field surveys of foxes naturally infected with E. multilocularis.

A high prevalence of larval Echinococcus multilocularis (Em) infection was found in zoo primates in Hokkaido, Japan. In October 1997, a Japanese monkey (Macaca fuscata) died and histopathologically diagnosed as alveolar hydatidosis. Serum samples were collected from the remaining Japanese monkeys and examined for antibodies against Em by enzyme-linked immunosorbent assay and western blotting. Serological tests showed 12 more animals of the remaining 57 monkeys were possibly infected. Ultrasonography revealed that nine of these 12 animals had a cystic lesion in the liver. The band patterns of western blotting in the monkeys were very similar to those in human.

Five animals in a colony of cynomolgus monkeys ( Macaca fascicularis) died or were euthanatized because of alveolar echinococcosis, during a period of 5 years. The remainder of the colony was screened for possible infection with Echinococcus multilocularis, using serology and ultrasonography. A total of 46 animals out of a group of 55 were examined. The presence of anti-Em2 antibodies analyzed with enzyme-linked immunosorbent assay was demonstrated in 3 monkeys. In 2 of these 3 monkeys, multilocular structures compatible with metacestodal cysts in the liver were identified, using ultrasonography. The presence of alveolar echinococcosis was subsequently confirmed at postmortem examination in 1 animal. The other animals are still alive. Two other monkeys were negative in the serological examination but had cystic structures in the liver, which were identified as bile duct cysts at postmortem examination in 1 animal. The other monkey is still alive. These findings suggest that serology for antibodies against the Em2 antigen may represent a useful method in identifying animals that might be infected with E. multilocularis and are therefore at risk of developing fatal alveolar echinococcosis.

THE recent excellent article by Barlow and others (2011) describing Echinococcus multilocularis infection in an imported European beaver (Castor fiber) illustrates the invaluable role that the Animal Health and Veterinary Laboratories Agency (AHVLA) plays in identifying emerging zoonotic diseases. It also illustrates how easily, had the owner buried the liver along with the rest of the carcase, the opportunity for making a diagnosis would have been missed. The authors state that the affected beaver had been trapped in an area of Bavaria where beavers are also culled for their pelts and for human consumption. The trappers were said to have observed gross liver lesions consistent with E multilocularis infection in around 10 to 20 of 400 culled beavers. In view of this history, and the fact that at least 49 animals from the affected population have been imported into the UK in the past 10 years (Barlow and others 2011), one might reasonably ask what health screening is required for such importations. The answer would appear to be nil. European Union legislation requires that live animals are traded freely between member states but, as far as we can determine, there is no statutory requirement for health checks, either before or after importation. Once in the UK, animals such as …

The study was conducted to evaluate a mAb-based coproantigen detection assay for monitoring fox prevalence of Echinococcus multilocularis infections in the Shiretoko National Park in Hokkaido, Japan. Eight fox families, each consisting of 2–4 adults and their pups, were selected because their territories have been determined. Faeces of each family (total n=537) were collected monthly from April to October, 1994. Detection of coproantigen and taeniid eggs was recognized in 58 and 27 faeces, respectively, but mostly restricted in 1 family, in which coproantigen ELISA OD values had dual peaks, one in June and the other in October, whereas taeniid eggs were detected only from April to July. Fox pup faeces (n=51) collected around the dens used by the positive family were all coproantigen and taeniid egg negative except for 1 faeces. These results suggest that the prevalence and infection pressure in the study area were low and the infected family terminated the infection in the summer and acquired a new one in the early autumn, 1994. This monitoring method for fox infection will be a practical management tool for E. multilocularis infection, especially at the tourist spots in Hokkaido where close contact of fox with humans is frequently observed.

Publisher Summary Echinococcus multilocularis was definitively established as an independent species by Vogel's exact morphological and biological investigations, including the completion of the life cycle of the parasite in experimentally infected hosts. The natural life cycle of E. multilocularis is uniform, although the host assemblages universally differ in accordance with faunal changes southwards from the Arctic. This fact is the principal determinant of the prevalence and distribution of the parasite. Attempts to delineate the three approximate geographical ranges of E. multilocularis have been made but exact distributional data are incomplete. Nevertheless, the geographical distribution of E. multilocularis seems to be uniquely restricted to the northern hemisphere. Alveolar echinococcosis (AE) of humans is biologically comparable to the disease in the natural intermediate hosts. The primary localization of E. multilocularis metacestodes (larvae) in humans (as well as in natural intermediate hosts) is almost exclusively in the liver. Local extension of the lesion and metastatic lesion formation in the lungs, brain, and other organs can follow. This chapter presents the immunological aspect of E. multilocularis and also discusses various diagnostic techniques. New developments in the diagnosis of and vaccination against E. multilocularis are also discussed, but the major and crucial aspect remains concentrated on the identification of E. multilocularis antigens to protect hosts.

The occurrence of Echinococcus multilocularis is reported in India for the first time. The patient was a young man, various clinical diagnoses were made and he finally died after an attempted membranotomy for suspected membranous obstruction in the inferior vena cava. Autopsy revealed classical E. multilocularis infection of the liver with direct spread of the inferior vena cava, the right atrium and through the diaphragm into the base of the left lung. It also had caused an outflow tract obstruction to the hepatic venous flow by direct physical pressure distorting the proximal intrahepatic portion of the inferior vena cava. In addition the patient had multi-valvular lesions of rheumatic origin and a terminal infective endocarditis due to staphyloccal infection.